The present invention relates to a flow control device.
Conventional flow control devices comprise, for example, a spindle having a handle at its upper end, a disk and an externally threaded portion in screw-thread engagement with an internally threaded portion of a case having a disk seat therein. The disk is pressed against the seat or moved away therefrom by rotating the handle to close or open a flow channel extending through the case. However, the device has the problem that the seal face of the disk becomes indented during use for a long period of time, displacing the handle when the disk is closed, or that the disk closing handle position changes owing to a machining error involved in the fabrication of the device, consequently influencing the opening-closing operation of the device. Further with the conventional device, it is likely that the operator will tighten up the handle excessively to produce an indentation in or cause damage to the seal face of the disk, thereby aggravating the above problem.